Three workouts a week for the last six months? Check.

Good food choices for 75% of your meals each week? Check.

Staying hydrated with water, not sugary juices and soda? Check.

But, still, your progress has stalled. You’re leaner than you used to be, but for the last couple of months you’ve noticed results slow and your energy levels decline.

The likely culprit? Sleep.

It’s still common for over-achiever types to wear “I only need four hours a night” like a badge of honor, like something worthy of praise. This association between high productivity and low sleep is unfortunate, because while it can work for a little while—if you have enough caffeine to stay functional—the research is very clear: human beings need seven to nine hours of high-quality sleep a night to function at their best.

There’s a surprising amount of research on the topic of sleep, and if you're interested in that type of thing we've linked to a load of studies in the text below, but for the purposes of this article, we’ll keep things short and sweet and stick to the fitness-related issues with insufficient sleep.

Sleep and Fat Loss

Not getting your seven to nine hours a night makes it really difficult for your body to shed fat. Physiologically, a cascade of things happen, none of them good:

Science-y version: Our ability to manage glucose and our sensitivity to insulin are dysregulated, our cortisol (a stress hormone) levels are elevated, and even your ghrelin and leptin (hormones that regulate hunger and satiety) responses are out of whack.

Real-people talk: Your body doesn’t signal ‘fullness’ and ‘hunger’ appropriately, your body does a poor job at dealing with sugar, and you’re more stressed out than you should be—all of which work against your fat loss efforts.

Unfortunately, even if you’re eating a restricted diet, the research suggests that it’s significantly harder to lose weight if you’re sleep deprived. You’re more likely to give in to temptation and eat unhealthy food, and overall, you have a higher chance of being obese.

Sleep and Performance

This one probably doesn’t come as a surprise, but everything from how much weight you can lift and how fast you can run, to your coordination and reaction time are significantly negatively impacted by sleep deprivation. This is especially the case if you’re chronically sleep deprived (hint: do you wake up feeling tired most mornings?). To make things worse, you’re also more likely to get injured during physical activity if you’re sleep deprived.

Instead of giving your body the time to recover, repair and come back stronger from a decent night's sleep, sleeping too little puts you in a position where you can’t get as much benefit from each workout, and you’re at unnecessary risk of injury. No bueno.

Sleep and Overall Health

Poor quality sleep can also impair other important areas, like cognitive function, which could affect everything from job performance to general decision-making ability. And, even more pertinent to the times we currently live in, insufficient sleep can have negative effects on both your mental health and your immune system function.

It’s alarmingly clear: sleep is just as important as exercise and nutrition when it comes to getting results. So perhaps we could all benefit from redirecting some of our ‘meathead energy’ (the part of you that wants to smash another session) towards the subtler art of becoming a sleep ninja.

How to get better sleep

If we’ve convinced you and you’re considering cleaning up your sleep habits, here are three simple steps you can take:

1. Try to wake up and go to bed at the same times each day. This will set a rhythm for your body that it can get used to.
   
2. Avoid consuming caffeine after 2pm. Some sleep experts recommend even more stringency than that, but we’ve found that 2pm is doable for nearly everyone. Note: it’s not just coffee—many teas have caffeine in them, so do a quick search online beforehand.
   
3. Stop looking at screens at least an hour before bed. The blue light exposure from our phones, laptops and TVs tend to throw our natural circadian rhythm out of whack, making it harder to fall asleep. Again, some sleep experts recommend even more restrictive guidelines than this, but one hour should be doable for most of us. After all, the internet will still be there in the morning.

Key takeaway/TLDR: get your seven to nine hours whenever you can!

Sleep hard.